Fuel; Gasoline Octane; Gasoline Specifications; California Fuel - Pontiac Montana SV6 2008 Owner's Manual

Fuel

Use of the recommended fuel is an important part of the
proper maintenance of your vehicle. To help keep the
engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies your
vehicle's engine. The VIN is at the top left of the
instrument panel. See Vehicle Identification Number
(VIN) on page 5-98.
If your vehicle has the 3.9L V6 engine (VIN Code W only),
you can use either regular unleaded gasoline or ethanol
fuel containing up to 85% ethanol (E85); also see Fuel
E85 (85% Ethanol) on page 5-6. If your vehicle has the
3.9L V6 engine (VIN Code 1), use only regular
unleaded gasoline.

Gasoline Octane

Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you might notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. If you are using gasoline rated at 87
octane or higher and you hear heavy knocking,
the engine needs service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or
CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines
containing MMT. See Additives on page 5-6 for
additional information.

California Fuel

If your vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specifications. See the underhood
emission control label. If this fuel is not available in
states adopting California emissions standards,
your vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission control system
performance might be affected. The malfunction indicator
lamp could turn on and your vehicle might fail a
smog-check test. See Malfunction Indicator Lamp on
page 3-42. If this occurs, return to your authorized
dealer/retailer for diagnosis. If it is determined that the
condition is caused by the type of fuel used, repairs might
not be covered by your warranty.
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